diff options
| -rw-r--r-- | logikorr.lisp | 72 |
1 files changed, 45 insertions, 27 deletions
diff --git a/logikorr.lisp b/logikorr.lisp index 441c83d..6d595d5 100644 --- a/logikorr.lisp +++ b/logikorr.lisp @@ -9,6 +9,9 @@ (last-name "" :type (or string null)) (first-name "" :type (or string null))) +(defvar *database* #p"/Users/mulk/Dropbox/Projekte/Logikorr/blatt3.txt") +(defvar *lock* (merge-pathnames #p".mulk-db-lock" *database*)) + #+(or) (defun create-student-id () (1+ (reduce #'max (find-students) :key #'student-id :initial-value -1))) @@ -16,26 +19,40 @@ (setq *hunchentoot-default-external-format* (flexi-streams:make-external-format :utf-8)) +(defmacro with-data-lock (() &body body) + `(call-with-data-lock (lambda () ,@body))) + +(defun call-with-data-lock (thunk) + (let (lock) + (unwind-protect + (progn + (loop until (setq lock (open *lock* :direction :output :if-exists nil :if-does-not-exist :create))) + (funcall thunk)) + (progn (ignore-errors (delete-file *lock*)) + (ignore-errors (close lock)))))) + + (defun find-students () - (with-open-file (in "/Users/mulk/Dropbox/Projekte/Logikorr/blatt3.txt" :external-format :utf-8) - (loop for line = (read-line in nil nil nil) - with id = 0 - while line - unless (equal (remove #\Space line) "") - collect (let* ((name line) - (score-line (read-line in t)) - (score (read-from-string score-line)) - (comma (position #\, name)) - (last-name (if comma (subseq name 0 comma) nil)) - (first-name (if comma (subseq name (+ comma 2)) name))) - (make-student :id id - :score (make-array (list (length score)) - :initial-contents score - :adjustable t - :fill-pointer t) - :last-name last-name - :first-name first-name)) - and do (incf id)))) + (with-data-lock () + (with-open-file (in *database* :external-format :utf-8) + (loop for line = (read-line in nil nil nil) + with id = 0 + while line + unless (equal (remove #\Space line) "") + collect (let* ((name line) + (score-line (read-line in t)) + (score (read-from-string score-line)) + (comma (position #\, name)) + (last-name (if comma (subseq name 0 comma) nil)) + (first-name (if comma (subseq name (+ comma 2)) name))) + (make-student :id id + :score (make-array (list (length score)) + :initial-contents score + :adjustable t + :fill-pointer t) + :last-name last-name + :first-name first-name)) + and do (incf id))))) (define-easy-handler (show-main-page :uri "/") () (let ((students (find-students))) @@ -173,14 +190,15 @@ div.autocomplete ul li { (define-easy-handler (update-student-score :uri "/update-student-score") (id score-number score) - (let ((student (find-student-by-id (parse-integer id))) - (index (parse-integer score-number))) - (loop while (<= (length (student-score student)) index) - do (vector-push-extend 0 (student-score student))) - (setf (elt (student-score student) index) - (let ((*read-eval* nil)) - (let ((score (read-from-string score))) - (check-type score number))))) + (with-data-lock () + (let ((student (find-student-by-id (parse-integer id))) + (index (parse-integer score-number))) + (loop while (<= (length (student-score student)) index) + do (vector-push-extend 0 (student-score student))) + (setf (elt (student-score student) index) + (let ((*read-eval* nil)) + (let ((score (read-from-string score))) + (check-type score number)))))) "\"OK\"") (define-easy-handler (add-student-score :uri "/add-student-score") |